裸燕麦米和燕麦粉加工所得麸皮中β-葡聚糖和酚酸的分布

选取具有代表性的裸燕麦品种,分析燕麦麸皮和胚乳所占的比例和微观结构特征;同时分析β-葡聚糖和酚酸在燕麦麸皮（果皮、种皮＋糊粉层）和胚乳中的分布,并验证了现有燕麦米和燕麦粉主流加工方式的适宜程度。结果表明,在所选裸燕麦品种中,β-葡聚糖均富集在麸皮中,质量分数达8.57%,约是胚乳中含量的4.5?倍;麸皮中p-香豆酸和阿魏酸的含量分别达0.099?mg/g和1.00?mg/g,分别是胚乳中相应含量的24?倍和48?倍;在麸皮中,果皮中p-香豆酸和阿魏酸含量分别约为种皮＋糊粉层中的13?倍和2.7?倍。研磨制燕麦米所得第2道麸皮中,β-葡聚糖质量分数平均为1.7%,远小于麸皮中的平均含量,加工程度适宜;而燕麦制粉所得第4道和第5道麸皮,β-葡聚糖质量分数达6.73%和7.80%,接近糊粉层中β-葡聚糖含量,加工过度。综上可知,利用分析燕麦加工所得麸皮中葡聚糖和酚酸含量,可初步判定燕麦米和燕麦粉的加工程度,为其加工提供技术支撑。     

Processing and composition of wild oat groats (Avena fatua L.)

Wild oats, a common weed contaminant in commercial grain, were investigated as a potential food grain since large quantities are recovered in cleaning plants. Pure wild oats were separated effectively from mixed feed oat samples using thickness graders in combination with indent separators. The hulls were removed by impact hullers and air aspiration to yield an attractive groat which could be further processed into oat flakes or milled into flour and bran components.The wild groat contained over 20% protein, 8% lipid and 55% starch, and was rich in essential minerals and vitamins. The yield of flour to bran was 60:40 and their respective protein contents were about 16% and 25%. Since the wild oat proteins, like those in the common groat, contain nearly 4% of lysine and nutritionally adequate levels of other essential amino acids, the wild groat appears to be an excellent alternative source of dietary protein. Specific applications would be as a protein and energy constitutent in infant foods, breakfast cereals and low-allergenic diets, and as a source of oat bran for cardiac patients.     

Influence of fibre from different cereals on the rheological characteristics of wheat flour dough and on biscuit quality

Demand for health oriented products such as sugar-free, low calorie and high fibre products is increasing. One such recent trend is to increase the fibre content in food products to overcome health problems such as hypertension, diabetes, and colon cancer, among others. Consumption of high fibre products consisting of indigestible cellulose, hemicellulose, lignin and gums have several health benefits. Apart from these benefits, β-glucan-rich fibres have the benefit of reducing the absorption of glucose. Fibre sources from wheat, rice, oat and barley were used to study their influence on rheological characteristics of wheat flour dough and biscuit making quality. Ash, total protein and dietary fibre content of bran samples ranged between 4% and 10%, 12% and 14% and 20.4% and 49.5%, respectively. Farinograph characteristics of the wheat flour-bran blends showed increase in water absorption from 60.3% to 76.3% with increase in the level of bran from 0% to 40%. The resistance to extension values as well as extensibility of the dough decreased with increase in the bran level. The spread ratio of the biscuits prepared from wheat, rice and oat bran blends decreased from 8.38 to 7.52, whereas the same increased to 9.3 for biscuits prepared from barley bran blends. The breaking strength values of biscuits ranged between 1.34 and 3.83 kg. Highly acceptable biscuits could be obtained by incorporating 30% of oat bran or 20% of barley bran in the formulation.     

Oat Gum and β-Glucan Extraction from Oat Bran and Rolled Oats: Temperature and pH Effects

The extractability of oat gum from oat bran and rolled oats was studied using 12 treatment combinations in a factorial design (2x3x4x2) i.e. 2 oat products; 3 pH (8.0–10.5); 4 temperatures (5O–70°C); 2 replications. The extraction procedure involved: (a) alkaline treatment of flour and removal of starch residue; (b) isoelectric precipitation of protein residue [namely, protein concentrates (PC)]; (c) and alcohol precipitation of oat gum/β-glucan and collection of gum by centrifu-gation. Extracted oat gum ranged from 2.99–6.28% for oat bran and 1.82–5.24% for rollcd oats whereas β-glucan (in gum) ranged from 70–89% and 50–68%, respectively. Protein contents of the PC from oat bran was 69–91% and rolled oats 66–89%. Correspondingly, starch content of residues ranged from 30–63% and 61–47%. Oat gum/β-glucan extracted at pH 9.2/50°C or pH 10.5/50/55°C showed little or no starch contamination.     

燕麦麸皮对馒头品质的影响

将不同比例的燕麦麸皮添加到小麦粉中,研究其对面团流变学特性和对馒头品质的影响。实验结果表明,向面粉中适量地添加燕麦麸皮,蒸制出的馒头其体积、质量和风味都有所增加,感官评分提高,表面变得光滑、对称、挺立,具有球形感,且内部气孔细小均匀。燕麦麸皮在不同添加量的条件下所制得的馒头感官评分结果为:燕麦麸皮添加量为5%时,馒头感官评价得分最高。相同添加量下的燕麦麸皮和小麦麸皮所制得馒头感官评分结果为:添加量为5%的燕麦麸皮所制的馒头感官评分结果高于添加量为5%的小麦麸皮所制的馒头感官评分结果。     

Exploiting blackcurrant juice press residue in extruded snacks

Extrusion process was developed to exploit blackcurrant juice press residues from industrial side-streams. Press residues obtained from conventional enzymatic pressing, with high content of fiber and seed oil, and novel non-enzymatic juice processing, with high content of sugars, fruit acids and anthocyanins, were extruded with barley flour, oat flour or oat bran. The recipes consisted of blackcurrant press residues (30%), cereal materials (40%) and potato starch (30%) and small amount of sugar and salt. When compared to enzymatic press residue and oat bran, the novel non-enzymatic press residue extruded with barley or oat flour had higher expansion, lower hardness and density, higher redness (a*), lower pH, and higher contents of fructose, glucose and fruit acids, all contributing positively to liking of texture, appearance, and flavor as well as berry-like experience. These characteristics were obtained with more gentle processing parameters, consisting of a lower total mass flow, screw speed and barrel temperature. Female consumers gave lower ratings in flavor, appearance and overall pleasantness for blackcurrant snacks than males. The study presented a sustainable way of utilizing industrial press residues from different processes of berry juice pressing for production of healthy snacks and breakfast cereals.     

Survival of Lactobacillus casei (LC-1) adhered to prebiotic vegetal fibers

This study evaluated the survival of Lactobacillus casei (LC-1) when adhered to four different dehydrated prebiotic fibers. After vacuum drying in oat bran with 9% β-glucan and green banana flour, LC-1 viability was 79% and 76%, respectively. Scanning electron microscopy images revealed no morphological changes in the cells adhered to these fibers, and the addition of trehalose as a cell protectant had a positive and significant effect on the survival of LC-1. At different storage temperatures, oat bran had the highest stability as well as in simulated gastrointestinal conditions, where LC-1 that adhered to the oat bran had greater viability (7.1 log CFU g^? 1) than in the free form (2.4 log CFU g^? 1). In the sensory evaluation, the probiotic oat bran added to a dairy fruit beverage was well accepted by consumers.Industrial relevanceThe diversification of food products and the growing interest in health life requires from food industry innovations and new products for this. Probiotic cultures into non-dairy products is still an innovation and a challenge to the functional food segment. The development of an oat bran with LC-1 adhered is important for the functional food industries because the probiotic can be viable during dehydration and storage at room temperature. In addition the LC-1 is protected under simulated gastrointestinal conditions without compromising sensory acceptability.     

三种粗粮粉体外调节肠道菌群的作用研究

通过在体外模拟构建消化和发酵体系,研究不同来源的三种麸皮(小麦麸皮、黑小麦麸皮和燕麦麸皮)配制成的粗粮粉对肠道菌群调节作用的影响。采用高通量测序技术16S rRNA对肠道菌群的多样性和组成进行分析,结果表明,粗粮粉发酵后微生物多样性降低,肠道菌群组成发生了较大变化,拟杆菌门比例下降,厚壁菌门比例升高,代谢产生的短链脂肪酸含量显著增多(p<0.05);其中,燕麦粗粮粉促进双歧杆菌体外增殖的效果优于其他两组粗粮粉,分别是小麦粗粮粉和黑小麦粗粮粉的1.45和2.14倍。本研究为调制加工性能好、保健价值高的粗粮粉配方提供了理论依据。     

Short-chain fatty acid content and pH in caecum of rats given various sources of carbohydrates

The caecal content of short-chain fatty acids (SCFA; acetic, propionic and butyric acid), caecal pH, fermentability and dry matter digestibility (DMD) were examined through balance experiments in rats fed 11 various indigestible carbohydrates. The following carbohydrate sources were incorporated into test diets: cellulose, oat husk, wheat bran, oat bran, pea fibre, linseed fibre, low methoxylated (LM)-pectin, guargum, β-glucans, neosugar and raffinose. The indigestible carbohydrates, except for those in wheat bran, oat husk and cellulose, were highly fermented, ie > 90%. Caecal pH varied between 5·6 and 7·8, with neosugar and raffinose causing the lowest pH and the fibre-free diet and the diet with oat husk the highest. The caecal pool sizes of SCFA were highest with raffinose, β-glucans, LM-pectin, guargum and linseed fibre (335-400 μmol) while pea fibre, wheat bran, oat bran and neosugar gave intermediate levels (137–227 μmol). The pool size with oat husk and cellulose was similar as with the basal diet (45–64 μmol). A high proportion of propionic acid was obtained with guargum and linseed fibre, whereas acetic acid was the predominant product in case of LM-pectin. On the other hand, linseed fibre gave a remarkably low proportion of butyric acid. The quantity fermented and caecal pH correlated well to the amount of SCFA with most materials (r = 0·96 and r = ?0·87, respectively), an exception was neosugar and in case of fermentability also oat bran. DMD values with most of the easily fermented carbohydrates were high (>96%). Exceptions were diets with β-glucans and oat bran which caused low DMD values, about 93%. It is concluded that indigestible carbohydrates may differ in ability to lower caecal pH and to form SCFA during fermentation.     

Maize bran/oat flour extruded breakfast cereal: A novel source of complex polysaccharides and an antioxidant

A maize bran/oat flour extruded breakfast cereal was developed as a novel source of an antioxidant and complex polysaccharides. Six levels of maize bran/oat flour were formulated (0, 10, 20, 30, 40 and 50%, w/w). The breakfast cereal containing 30% maize bran was the most accepted by consumers. A 100 g serving of this cereal formulation provides 0.2 g of ferulic acid, and 8 g of complex polysaccharides, which includes 1.2 g of β-glucans and 6.8 g of arabinoxylans. This cereal breakfast could be an alternative to maize bran, which is a by-product scarcely used for human consumption.     

Varied Composition of Tocochromanols in Different Types of Bran: Rye,Wheat, Oat,Spelt, Buckwheat,Corn, and Rice

The profiles of tocopherol (T) and tocotrienol (T3) homologues in 37 samples of seven different types of bran (rye, wheat, oat, spelt, buckwheat, rice, and corn), available on the Polish market, were studied. Tocochromanols were identified and quantified by reverse phase-high-performance liquid chromatograph/fluorescence detector and reverse phase-ultra performance liquid chromatography-electrospray ionization/mass spectrometry. Only rice bran contained all eight tocochromanol types. Corn bran lacked β-T3; rye, wheat, oat, and spelt bran lacked γ-T3 and δ-T3; and buckwheat bran lacked β-T3, γ-T3, and δ-T3. In buckwheat and corn bran tocopherols predominated (98 and 78%, respectively); whereas rye, wheat, oat, spelt, and rice bran were rich in tocotrienols (78, 76, 66, 87, and 66%, respectively). The average total tocochromanol contents in the oat, corn, spelt, buckwheat, wheat, rye, and rice bran were 5.5, 16.2, 15.8, 14.7, 12.8, 10.7, and 9.1 mg/100 g of dry weight, respectively. Tocochromanol concentrations in samples of the same type bran from different sources varied considerably. Better labeling of bran products to reflect this variation would assist with control of vitamin E daily dietary requirements.     

WHEAT BRAN (TRITICUM AESTIVUM): COMPOSITION, FUNCTIONALITY AND INCORPORATION IN UNLEAVENED BREAD

High fiber Chapathi, an Indian unleavened bread incorporating different levels (5–15%) of wheat bran to wheat flour was prepared and evaluated for acceptability and farinograph characteristics. Whole wheat flour, wheat bran and its differently milled fractions were analyzed for chemical composition and functional properties. The water absorption capacity of bran was slightly lower than that of flour and did not increase as a function of time. The bran incorporated doughs were difficult to knead and sticky with no change in rolling properties. Farinograph characteristics revealed an increase in dough development time and a decrease in mixing tolerance index as the level of incorporation of bran increased. Wheat bran incorporated products scored lesser for the sensory quality attributes than controls. The differences were statistically significant for products prepared with 10% and 15% bran and not significant for products prepared with 5% level of bran. It can be concluded that wheat bran can be incorporated up to a level of 5% for preparation of high fiber phulkas or chapathis without affecting sensory quality.     

High-Protein Oat Flour Functionality Assessment in Bread and Sausage

The effectiveness of high-protein oat flour, a by-product of an oat starch process, was studied in bread baking and sausage processing. Its impact on sensory properties of products was assessed. High-protein oat flour enhanced water absorption and mixing stability of the dough. Some weakening of dough was found as indicated by a decrease in extensibility and resistance. Addition of oat flour increased loaf volume, enlarged grain size and darkened crumb color. It also caused some off-odors assessed as a decrease in “cleanness” of aroma. Sausages containing high-protein oat flour formed an external gel-like layer under the casing during processing, probably caused by the low pH of the flour. In sensory analyses the sausages were judged less firm and juicy than the control. The “cleanness” of odor and flavor of the sausages was distinctively diminished. Cereal products should be considered the primary products for utilization of high-protein oat flour.     

超声辅助冻融法提取燕麦麸β-葡聚糖

为探究燕麦麸中β-葡聚糖的超声辅助冻融提取方法,采用超声浸提、蒸发浓缩、反复冻融从燕麦麸中提取β-葡聚糖,研究燕麦麸β-葡聚糖的提取得率、纯度、持水性和黏度,同时用紫外和红外光谱对提取的燕麦麸β-葡聚糖进行结构表征。结果表明:超声辅助提取时,当料液比为1∶20(g/mL)、超声功率为500 W、提取温度为55℃、提取时间为50 min,可将提取液蒸发浓缩至体积的4.0%,反复冻融2次,燕麦麸β-葡聚糖的得率为6.0%,β-葡聚糖纯度可达到82.3%,其持水率为307.6%,燕麦麸中提取的β-葡聚糖紫外光谱、红外光谱和β-葡聚糖的标准图谱一致。超声辅助冻融法提取可得到较高纯度、持水率和黏度的燕麦麸β-葡聚糖。     

Pasting and rheological properties of quinoa‐oat composites

Quinoa (Chenopodium, quinoa) flour, known for its essential amino acids, was composited with oat products containing β‐glucan known for lowering blood cholesterol and preventing heart disease. Quinoa–oat composites were developed and evaluated for their pasting and rheological properties by a Rapid Visco Analyzer (RVA) and an advanced rheometer. All quinoa–oat composites showed increased pasting viscosities with increases in oat contents. The elastic modulus G′ and viscous modulus G″ for all quinoa–oat composites were higher than quinoa, suggesting that oat products increased the viscous properties of composites. Shear‐thinning properties were observed for all the composites. Improved water‐holding capacities (WHC) were found for the composites containing quinoa with nutrim or oat bran concentrate compared to quinoa alone. All the WHC of quinoa–oat composites were increased with the higher amounts of oat components. These quinoa–oat composites have improved nutritional value and texture qualities suitable for functional food applications.     

The gastrointestinal metabolic effects of oat product based-β-glucan in mice

Most physiologicalstudies studies of oat beta (β)-glucan have shown positive effects on regulation of blood glucose and lipid metabolism related to β-glucan metabolism in the gastrointestinal tract. The effects of oat β-glucan (OG), oat bran (OB), oat flour (OF), and oatmeal (OM) containing different levels of β-glucan on digestibility and degradation were investigated in normal mice. Chyme viscosity, the gastric emptying rate, the gastrointestinal transit rate, the activities of intestinal digestive enzymes, the levels of plasma cholecystokinin (CCK) and motlin (MOT), and degradation of β-glucan in oat products were determined. β-glucans from different oat products increased intestinal chyme viscosity, delayed gastric emptying, promoted enterokinesia, decreased amylase, trypsin, lipase, and Na⁺, K⁺-ATPase activities, and promoted secretion of CCK and MOT, especially for oat derived β-glucan.     

Fibre-rich additives--the effect on staling and their function in free-standing and pan-baked bread

BACKGROUND: The use of dietary fibre in bread products is increasing because of consumer demand for healthier products. However, an increase in dietary fibre level changes the rheological properties of the dough and also the quality properties of the final bread product. In this study, effects on dough and bread staling were followed after replacing 3% of wheat flour by fibre‐rich additives (fine durum, oat bran, rye bran and wheat bran). Free‐standing and pan‐baked loaves were baked to compare the influence of baking method and loaf shape. RESULTS: All additives increased dough stability, with oat bran giving the greatest stability and longest development time. Parameters measured during storage were distribution, migration and loss of water, cutability, crumbliness, firmness and springiness. Furthermore, amylopectin retrogradation and amylase‐lipid complex formation were assessed. Oat bran provided similar or better results than the control for all staling parameters, while other additives gave no general improvements. Cutability reached a plateau when crumb firmness was ≥ 4 N. CONCLUSION: Small amounts of fibre‐rich additives had a significant influence on staling. However, the baking method (free‐standing or pan‐baked bread) had a greater impact on staling than the additives, thus displaying the importance of the baking method. Cutability was found to be related to firmness. Copyright © 2011 Society of Chemical Industry     

Sorption of copper,zinc and cobalt by oat and oat products

We determined copper, zinc and cobalt sorption by oat and its products under variable pH conditions as well as the content of neutral dietary fiber (NDF) and its fractional composition. Adsorbents in a model sorption system were: oat, dehulled oat, oats bran and oats flakes. Three various buffers (pH 1.8, 6.6 and 8.7) were used as dispersing solutions. Results collected during this study indicate that copper, zinc and cobalt sorption is significantly affected by the type of cereal raw material. Zinc and copper ions are subjected to higher sorption than cobalt ions. Examined metal ions were subjected to high sorption under conditions corresponding to the duodenum environment (pH 8.7( regardless of the kind of adsorbent. A little lower sorption capacity is observed under conditions close to the neutral environment, while the lowest one is found in environment reflecting conditions of stomach juice (pH 1.8). Zinc ions are bound intensively by dehulled oat, while oats flakes bound mostly copper and cobalt, independently on environmental conditions. Contents of dietary fiber in oat, dehulled oat, oat bran and oat flakes were: 40.1, 19.3, 20.3 and 14.3%, respectively. The dominating fraction in all oat products was the fraction of hemicelluloses. The content of remaining fractions varies in dependence on the product.     

Sorption of copper,zinc and cobalt by oat and oat products

We determined copper, zinc and cobalt sorption by oat and its products under variable pH conditions as well as the content of neutral dietary fiber (NDF) and its fractional composition. Adsorbents in a model sorption system were: oat, dehulled oat, oats bran and oats flakes. Three various buffers (pH 1.8, 6.6 and 8.7) were used as dispersing solutions. Results collected during this study indicate that copper, zinc and cobalt sorption is significantly affected by the type of cereal raw material. Zinc and copper ions are subjected to higher sorption than cobalt ions. Examined metal ions were subjected to high sorption under conditions corresponding to the duodenum environment (pH 8.7), regardless of the kind of adsorbent. A little lower sorption capacity is observed under conditions close to the neutral environment, while the lowest one is found in environment reflecting conditions of stomach juice (pH 1.8). Zinc ions are bound intensively by dehulled oat, while oats flakes bound mostly copper and cobalt, independently on environmental conditions. Contents of dietary fiber in oat, dehulled oat, oat bran and oat flakes were: 40.1, 19.3, 20.3 and 14.3%, respectively. The dominating fraction in all oat products was the fraction of hemicelluloses. The content of remaining fractions varies in dependence on the product.     

The effect of replacing fat with oat bran on fatty acid composition and physicochemical properties of meatballs

Oat bran was used as a fat substitute in the production of meatballs. The effect of oat bran addition on the fatty acid composition, trans fatty acids, total fat, some physicochemical and sensory properties of the samples was studied. Meatballs were produced with four different formulations; the addition of 5, 10, 15 and 20% oat bran. Control samples were formulated with 25% fat addition as in commercial production. The major fatty acids were cis-oleic, palmitic and stearic acid in all the meatball samples, those with oat bran added as well as the control. Meatballs containing oat bran had lower concentrations of total fat and total trans fatty acids than the control samples. Meatballs made with 20% oat bran had the highest protein, salt and ash contents, L value (lightness), b value (yellowness), and the lowest moisture content and a value (redness). There was no significant difference among the meatball samples with respect to sensory properties, and all samples had high acceptability.